function pllpc(t0)

% Copyright (c) 1995 by Philipos C. Loizou
%

global fFig tFig filename Srate fno nLPC   nChannels UpperFreq
global HDRSIZE center LPCSpec Dur filterA filterB Lfreq
global OVRL ymin ymax  clrCnt bl al ymin2 ymax2 WAV1 chrCnt lnCnt
global TWOFILES TOP filename2 HDRSIZE2 Srate2
global al2 bl2 filterA2 filterB2 DiffSrate wav prM
global  FIX_SCALE yMAX yMIN
global ftype ftype2 bpsa bpsa2 ctlFig MAPLaw
global ipk1 ipk2 ipk3 iapk1 iapk2 iapk3 iengy plt_type LPC_ONLY
global FFT_SET pFFT lpcParam fft_par SET_X_AXIS F_MAX x_max 
global XFFT XFFT_TIMES
global foha fore
global fftFreqs dBMag
global fb_sav   % used for saving the coeffs in a file
global oha ore opy opn ope

fftSize=512;

clr='ymcrgbw';  % define all  colors 'y'=yellow, 'm'=magenta ,etc
chr='ox*+';
lns='-:-.--';

pos = get(0, 'screensize'); % get the screensize
sWi = pos(3);
sHe = pos(4);


wi=round(0.5625*sWi);
he=round(0.4*sHe);
le=round((sWi-wi)/2)-5;

sratef=Srate;

if isempty(plt_type), plt_type='line'; end;


	if TWOFILES==1 & TOP==1
		fname=filename2;
		hdrs =HDRSIZE2;	
		nSamples=round(Dur*Srate2/1000);
		sratef=Srate2;
		bps=bpsa2;	% Bits per sample
		ftp=ftype2;
	else
		fname=filename;
		hdrs =HDRSIZE;	
		nSamples=round(Dur*Srate/1000);
		bps=bpsa;  % Bits per sample
		ftp=ftype;
	end
	
	fp = fopen(fname,'r');
	if fp<=0
	  error('Could not open input filename in pllpc.m');
	end
	

	offSet = t0*bps+hdrs;
	st = fseek(fp,offSet,'bof');
	
	inp = fread(fp,nSamples,ftp);
	[inp,ncount] = fread(fp,nSamples,ftp);
	if ncount<nSamples, nSamples=ncount;  
	end;
	if nSamples<20, 
	  fprintf('\nERROR in plotting the LPC spectra. The window was too small..\n\n');
	  fclose(fp); return;
	end
	
	fclose(fp);
   
%----------- Remove the DC bias------------
meen=mean(inp);
inp=inp-meen;


%---- Do some error checking on the signal level ---
if norm(inp,2) < 1.0e-7
  if meen < 1.0e-3
	meen=1.0e-3;
   end
   inp=inp+meen;
  engy=-100;
else
  engy=10*log10(norm(inp,2)^2);
end


if ~isempty(fFig) 
  invalid=0;
  eval('findobj(fFig);','invalid=1;');  
end

if  isempty(fFig) | invalid==1
	fFig = figure('Units', 'pixels', 'Position', [le 35 wi he],...
	'Menubar','None','NumberTitle','off','Name',...
	'LPC Spectra','WindowButtonDownFcn','puttext',...
	'Pointer','crosshair','Color','k');

else
	figure(fFig);

end

if isempty(ctlFig) %---- Draw the controls panel ------------
 drawctls;
end




% --check to see if the number of samples is greater than the FFT size

if FFT_SET == 1 
    fftSize= pFFT;
    if nSamples>fftSize
      errordlg('The frame size is larger than the FFT size.','WARNING','on');
    end
else

 if nSamples>fftSize
    fftSize=2*fftSize;
    if nSamples>fftSize, fftSize=2*fftSize; end
 end
end


if XFFT==1  % change the size of the FFT
   fftSize=fftSize*XFFT_TIMES;
end


fft2=fftSize/2;



if (LPCSpec == 1)   %----------------- Plot the LPC spectrum ----------------
     inpLP=inp;
     if lpcParam(2)==1  % use 1-st order pre-emphasis filter
        inpLP=filter([1 -0.95],[1],inp);      
         if lpcParam(1)==1
           inpLP=hamming(nSamples).*inpLP;  % Use hamming window
        end
     else % do not use pre-emphasis filter
       if lpcParam(1)==1
          inpLP=hamming(nSamples).*inp;    % Use hamming window
       end
     end
     
     
     [a,rxx] = ilpc(inpLP,nLPC);  % do LPC analysis
     Gain = rxx*a;  % LPC gain
     
     %if lpcParam(3)==1, a(2:nLPC+1)=((1.1).^[1:nLPC]).*a(2:nLPC+1);  end
	
    [H,F]= freqz(sqrt(Gain),a,fftSize,sratef);

else                		%--------------- Plot the FFT Spectrum ---------------
    fftFreqs = (0:fft2-1)/fftSize*sratef;
    fd=zeros(fftSize,1);
    if fft_par(2)==1 % use hamming window
       fd(1:nSamples)=hamming(nSamples).*inp;
    else  % use rectangular window
       fd(1:nSamples)=inp;
    end
    fd2= abs(fft((fd)));   
    fftMag = fd2(1:fft2);  
    if fftMag(1)<1E-8, fftMag(1)=fftMag(2)/10; end; % avoid log(0)
    dBMag = 20*log10(fftMag);  
end

    if (LPCSpec==1)
       fftFreqs = 0.5*(0:fftSize-1)/fftSize*sratef;
       fftMag=abs(H);
       dBMag = 20*log10(fftMag);
    end
    
    if OVRL<0
       hold on
	
	mb2=min(dBMag); mx2=max(dBMag); % -- LPC plot
	if (mb2 < ymin2), ymin2=mb2; end;
	if (mx2 > ymax2), ymax2=mx2; end;
	clrCnt=clrCnt+1;
	chrCnt=chrCnt+1;
	lnCnt=lnCnt+1;
	if lnCnt>2
     	   sclr= [lns(lnCnt:lnCnt+1)];
     	   lnCnt=lnCnt+1;
    	else
     	   sclr=[lns(lnCnt)];
    	end
	if (clrCnt==8), clrCnt=1; end;
	if (chrCnt==5), chrCnt=1; end;  
	if (lnCnt==6),  lnCnt=0; end;  
    else
		ymin2=min(dBMag); ymax2=max(dBMag);
	clrCnt=2; chrCnt=1; 
	lnCnt=1;
	sclr='-';
	hold off
    end
	

    if LPC_ONLY==0, subplot(2,1,1); 
    else	    subplot(1,1,1); end;

    if (OVRL<0), hold on, else hold off, end;
    set(gca,'LineStyleOrder',sclr);
   
    if LPCSpec==1
      h=plot(fftFreqs,dBMag);
      set(h,'color',clr(clrCnt));
   else
      if fft_par(1)==1, h=plot(fftFreqs,dBMag); set(h,'color',clr(clrCnt));
	else	
	   len=length(dBMag); db2=zeros(len,1); db3=zeros(len,1);
    	   db2(1)=dBMag(1);
    	   db2(2:len)=dBMag(1:len-1);
    	   db3(1:len-1)=dBMag(2:len); db3(len)=dBMag(len);
    	   ipks=find((dBMag > db2) & (dBMag > db3));
    	   rsl=sratef/fftSize; 
    	   pks=(ipks-1)*rsl; 

	   stem(pks,dBMag(ipks)); %-- plot only the peaks (harmonics)

	end
    end
     set(gca,'FontSize',9);
     set(gca,'Color','k');
     set(gca,'Xcolor','w'); 
     set(gca,'Ycolor','w');

 %
 %------- find the peaks in spectrum and display their values  ---------------
 % 
 if LPCSpec==1
    len=length(dBMag); db2=zeros(len,1); db3=zeros(len,1);
    db2(1)=dBMag(1);
    db2(2:len)=dBMag(1:len-1);
    db3(1:len-1)=dBMag(2:len); db3(len)=dBMag(len);
    ipks=find((dBMag > db2) & (dBMag > db3));
    rsl=0.5*sratef/fftSize; 
    pks=(ipks-1)*rsl; pklen=length(ipks);
    if pklen>1, set(ipk1,'String',sprintf('%d',round(pks(1))));
	        set(iapk1,'String',sprintf('%d',round(dBMag(ipks(1))))); end;
    if pklen>2, set(ipk2,'String',sprintf('%d',round(pks(2)))); 
	        set(iapk2,'String',sprintf('%d',round(dBMag(ipks(2))))); end;
    if pklen>3, set(ipk3,'String',sprintf('%d',round(pks(3))));
  	        set(iapk3,'String',sprintf('%d',round(dBMag(ipks(3))))); 
	else
	        set(iapk3,'String','');  set(ipk3,'String','');end;
 else
	set(iapk1,'String','');  set(ipk1,'String','')
	set(iapk2,'String','');  set(ipk2,'String','')
	set(iapk3,'String','');  set(ipk3,'String','')
 end;
    set(iengy,'String',sprintf('%d',round(engy)));
	
 
    if LPC_ONLY==0 % top display=FFT or LPC 	
      axis([0 Lfreq ymin2 ymax2+3])
    else %----- single display of FFT or LPC spectrum

      x_max=sratef/2; 
      if SET_X_AXIS==1, if F_MAX< x_max, x_max=F_MAX; end; end;
      axis([0 x_max ymin2 ymax2+3])
      xlabel('Frequency (Hz)');
    end

    set(gca,'LineStyleOrder',sclr);
    h=ylabel('Magnitude (dB)');  set(h,'FontSize',9);

    set(gca,'FontSize',9); 
    
   


%------------ create the menus now ----------

if isempty(prM)
xywh = get(fFig, 'Position');

% Buttons.
left = 6;
wide = 40;
top  = xywh(4) - 3;
high = 22;
if 9*(22+8) > xywh(4), high=17; end;
inc  = high + 8;


%--------Set up the Print and Save Menu --------------


 prM=uimenu('Label','Print');
     uimenu(prM,'Label','Portrait','Callback','prnt2(''portr'')');
     uimenu(prM,'Label','Landscape','Callback','prnt2(''landsc'')');
 prM2= uimenu('Label','Save');
       uimenu(prM2,'Label','Black/White Postscript','Callback','prnt2(''bwps'')');
       uimenu(prM2,'Label','Color Postscript','Callback','prnt2(''ceps'')');
       uimenu(prM2,'Label','Bit Map','Callback','prnt2(''bmp'')');
       uimenu(prM2,'Label','Windows Metafile','Callback','prnt2(''wmf'')');
       uimenu(prM2,'Label','Clipboard','Callback','prnt2(''clip'')');

uil=uimenu('Label','Label');
	uimenu(uil,'Label','Add Text','Callback','itext(''add'')');
	uimenu(uil,'Label','Delete Text','Callback','itext(''del'')');


optm=uimenu('Label','Options');
    	uf=uimenu(optm,'Label','Set Frequency Range');
		   uimenu(uf,'Label','Default','Callback','setpar(''range_def'')');
	 	   uimenu(uf,'Label','0-5 kHz','Callback','setpar(''range_5k'')');
		   uimenu(uf,'Label','0-4 kHz','Callback','setpar(''range_4k'')');
		   uimenu(uf,'Label','0-3.2 kHz','Callback','setpar(''range_32'')');

		oplp=uimenu(optm,'Label','LPC analysis');
	   owi=uimenu(oplp,'Label','Window');
		oha=uimenu(owi,'Label','Hamming','Checked','on','Callback',...
			   'setovr(''LPhamming'')');
		ore=uimenu(owi,'Label','Rectangular','Callback',...
			   'setovr(''LPrect'')');
	   opr=uimenu(oplp,'Label','Preemphasis');
		opn=uimenu(opr,'Label','No','Checked','on','Callback',...
			   'setovr(''LPnoPre'')');
		opy=uimenu(opr,'Label','Yes','Callback',...
			   'setovr(''LPyesPre'')');
		uimenu(oplp,'Label','Save LPC data in a file','Callback','savelpc');

 	opft=uimenu(optm,'Label','FFT analysis');
		uimenu(opft,'Label','Picket spectrum','Callback','setpar(''FFT_pick'')');
	 	uimenu(opft,'Label','Line spectrum','Callback','setpar(''FFT_line'')');
			ufs=uimenu(opft,'Label','FFT Size');
		   uimenu(ufs,'Label','Default','Callback','setpar(''size_def'')');
		   uimenu(ufs,'Label','x2','Callback','setpar(''size_x2'')');
         uimenu(ufs,'Label','x4','Callback','setpar(''size_x4'')'); 
         fowi=uimenu(opft,'Label','Window');
         foha=uimenu(fowi,'Label','Hamming','Checked','on','Callback',...
			   'setpar(''hamming'')');
         fore=uimenu(fowi,'Label','Rectangular','Callback',...
			   'setpar(''rect'')');


	
end

figure(fno);


